I have completed the calculations on over six different complete reports. The down side is that the first four are with the Merlin 45 at boost levels of +8.8 to 9.3 lbs./sq.in. As far as I can tell, when the Spitfire five was introduced it was cleared for +12 lbs./sq.in. for at least 3 minutes of combat. If the interest is there I could post the data from these reports, but it would not be representative of the full capabilities of the Spitfire Mk.V.

With that being said I'll start with the data from the R.A.E. graph covering the speeds of the Spitfire Mk.V at +9, +12 and +16 lbs.

A.&A.E.E. / Boscombe Down / Spitfire F. Mk. Vb W.3228 / Dated 5/25/43......."...has been fitted with a special Merlin 50 engine, on which the supercharger impellor was "cropped" to a diameter of 9.5"." The Maximum boost used in the trials was +18.2 lbs./sq.in.

Note: The standard wing Spitfire was put on the tail of a clipped wing Spitfire. In several cases the clipped wing Spitfire was able to evade so rapidly that it could reverse their positions in about 20 seconds.